Crucial MX100 Review: An SSD for the Masses

Crucial has dropped the price per gigabyte of SSD storage below the $0.5 mark and it is not a sale of old products. We're talking about a promising new model with high performance, excellent features and good reliability. What's the hitch? Let’s find out right now!

The SSD market is perhaps the most dynamic and competitive of any in today’s IT industry. It can change rapidly, requiring a flexible and long-term strategy from its players. Those who fail to follow its trends may quickly find themselves outplayed. The latest price war, for example, has already been the end of several SSD makers, including some well-known brands. Notwithstanding these vagaries, this market has its long-established leaders whose positions seem to be unshakable. There are five of them (Samsung, Intel, SanDisk, Micron, Toshiba) and theirs is a combined share of two thirds of the entire market. Incidentally, all of them are also manufacturers of NAND flash memory, so they can dictate the rules to other SSD makers.

However, there are only two companies, Samsung and Micron, that play the most important role when it comes to consumer-class SSD products. Samsung is the key innovator developing, implementing and promoting perspective technologies whereas Micron is busy pushing the prices down. This summer, both have made their next moves, offering new SSDs under their respective strategies. Samsung has released the high-performance 850 Pro, the world’s first mass-produced SSD with 3D flash memory. Micron, on its part, has rolled out the rather ordinary Crucial MX100 which only differs from its predecessor in using flash memory that features a more advanced manufacturing process. The product from Micron is the first to have made it to our labs, so we'll talk about it in this review.

It’s useless to look for any technological advances in Crucial-branded products, so we’d better take a look at its price tag first. Carrying on the glorious traditions of the legendary RealSSD C300, m4 and M500 models, the Crucial MX100 drops the price per gigabyte considerably below the $0.5 mark. Particularly, the 256GB version comes at a recommended price of only $110 whereas the 512GB version is priced at $225. By the way, that’s only about half the release price of the Crucial M500, so Micron has brought the price down by 50% in just 14 months!

The Crucial MX100 seems to be doomed to become the absolutely bestselling consumer-class SSD for the next few months. Relying on manufacturing advances, Micron has managed to continue its policy of price reduction, which makes its new product look like the best offer for price-conscious users (if we consider the recommended prices rather than the actual prices at your local retailer). Of course, we are always wary of tradeoffs in terms of speed or reliability. Crucial’s earlier SSDs were cheap and yet free from serious flaws, though. What about the MX100?

Specifications

So the Crucial MX100 is the first mass-produced SSD with Micron’s new 16nm MLC NAND flash memory. This memory was announced a year ago as the smallest MLC NAND devices with 128-gigabit dies. The advanced manufacturing process ensures the industry’s highest data storage density. Unfortunately, Micron doesn’t provide official data about the physical dimensions of the semiconductor dies but we estimate the size of a 128-gigabit 16nm die at 190 sq. mm. Thus, the transition to the more advanced technology lowers the manufacturing cost of MLC NAND flash memory by about 6% compared to Micron’s 20nm flash memory which is used in the Crucial M500 and M550 drives.

A 128-gigabit 16nm MLC NAND semiconductor die from Micron

It must be noted, however, that making flash memory cells smaller isn't always beneficial. A “thinner” manufacturing technology may reduce such an important parameter as endurance. Smaller flash memory cells can last through fewer rewrite cycles whereas the high component density may have a negative effect on stability due to memory cell crosstalk. Such things provoke certain apprehensions about the actual characteristics of the new 16nm MLC NAND flash.

Micron doesn’t tell anything about endurance but we know that Intel, being Micron’s manufacturing partner, helped Micron implement high-k materials when transitioning to the 20nm technology. That’s the explanation of the rapid miniaturization over the last few months: the new dielectric improves the scalability of the manufacturing process without compromising the end-product's endurance.

That’s why we think the majority of desktop users are going to be satisfied with the endurance of the 16nm flash memory. After all, the MX100 is specified to have the same endurance as Crucial's previous series. It lets you write up to 72 terabytes of data (or 40 gigabytes daily for 5 years). That’s the same specifications as we have with Crucial's M500 and M550 which have 20nm MLC NAND flash, so Micron seems to regard its new 16nm and old 20nm memory as comparable in terms of endurance. The Crucial MX100 comes with a 3-year warranty, which is standard for a mainstream SSD.

We’re focusing on the new 16nm memory just because it is the only significant innovation implemented in the new SSD. From the architectural point of view, the Crucial MX100 has the same hardware platform as its predecessor M550. Based on the Marvell 88SS9189 controller, it has a lot in common with the M550:

The Crucial MX100 is positioned differently, though. It is meant to replace Crucial’s previous entry-level solution M500 and is supposed to offer higher performance at a lower price. Until the M500 is sold out, its actual retail price may be lower, so you may want to check the older model out if price is your priority. The oldie M500 has one more advantage. This series includes a 1-terabyte version whereas the MX100 series is capped at 512 gigabytes. Crucial will only offer the more expensive 1TB M550 to users who need such a high storage capacity.

The MX100 series also lacks a 64GB version, so the full model range looks like follows:

Although we said that the Crucial MX100 has the same hardware platform as the M550, there's a significant difference between these two drives besides the flash memory manufacturing process. The fastest M550 models have both 64-gigabit and 128-gigabit memory whereas the MX100 comes with cheap 128-gigabit memory only. That’s why the Marvell 88SS9189 controller can reach its maximum level of interleave (with 32 MLC NAND dies) in the 512GB version of the MX100 drive and performs less efficiently in the lower-capacity versions.

So it is no wonder that the Crucial MX100 512GB is comparable in performance to the same-capacity M550 but the 128GB and 256GB versions of the MX100 are inferior to their M550 counterparts in terms of write speed - by up to 100%!

Interestingly, the 128GB version of the MX100 uses the older 20nm instead of the new 16nm memory. To ensure the specified 72-terabyte endurance with a typical write amplification coefficient of 2.5 requires flash memory with a rated 1500 rewrite cycles but Micron dares not guarantee it for its 16nm chips yet. We guess the 16nm memory will be installed into the 128GB model as well after the manufacturing technology has matured.